An existing mobile device, such as a mobile phone, may have all its functions and files displayed on a screen after startup. As for a file or program which can only be accessed with a corresponding authorization, a password may be set for it. However this kind of encryption may have a relatively lower security level.
The patent “Method for Realizing Related Mobile Communication Terminal Function by Fingerprint Recognition” (Application No.: 200910200922.6) discloses a security protection method using fingerprint recognition. Although the fingerprint recognition may be unique, it may still be risky because a fingerprint may be easily stolen due to fingers touching many things in daily life.